In about 1980, the compact disk (CD) was first introduced to the market jointly by Philips and Sony. The CD is initially developed for the household appliance consumer market instead of computer storage. However, thanks to the easy portability, safety and durability, multimedia nature, big storage capacity, and low manufacturing cost thereof, the CD has been quickly applied in the storing of huge amount of computer data. With the rapidly increased market demands for CDs, many big-scale firms have successively engaged in the production of CDs. As a result, the manufacturing of various kinds of CD-related products, such as storages, containers, and packaging boxes for CDs, is also prosperously developed.
On the other hand, with the popularity of CD-related products and the gradually saturated CD market, and the fact that many local CD-related firms are restricted by foreign patents and have to pay extremely high royalty for producing patented CDs. Therefore, for the purpose to survive in a business environment with high pressure of maintaining basic revenue and profit, a “meager profit” policy has become a new trend in the market. That is, it is a currently very important issue in the business field to develop ways for simplifying manufacturing process to upgrade product quality while effectively lowering the manufacturing and packaging costs.
A typical example of lowering manufacturing and packaging costs is found in Taiwan Patent Publication No. 00570029, which discloses a device for preventing a plurality of concentrically stacked and packaged CDs from deformation. The device includes a plastic film, at least one blank disk, and at least one back-up plate. The blank disk is positioned at an outer end of the stacked CDs, and the back-up plate is positioned between the blank disk and the stacked CDs. When packaging the stacked CDs, the plastic film is covered over an integral body of the stacked CDs, back-up plate, and black disk. In this manner, the CDs are protected against deformation, the time for packaging the CDs may be effectively shortened, and the packaging material may be effectively reduced.
In the above-described CD packaging manner, the packaged CDs are subject to damage caused by minor impact when the back-up plate, is too thin. FIG. 1 shows a somewhat improved back-up plate used in packaging stacked CDs. As shown, the back-up plate of FIG. 1 has a narrow peripheral wall to increase a thickness at a circumferential periphery of the back-up plate, and is provided with a plurality of reinforcing ribs radially extended from a central area of the back-up plate, so as to effectively increase the strength at two ends of the CD package to provide better protection of the packaged CDs against damage caused by minor collision or impact.
Since the above improved back-up plate is only strengthened along the circumferential periphery by the narrow peripheral wall thereof, the narrow peripheral wall of the back-up plate tends to break, crack, and/or collapse when the package of the stacked CDs is subjected to impact during transporting thereof. Even if the packaged CDs are not damaged by such impact, the broken peripheral wall of the back-up plate visible from outside the package would adversely affect an overall appearance of the package to even result in rejection of the packaged CDs.
It is therefore tried by the inventor to develop an improved disk protecting plate to overcome the drawbacks in the CD package protection of prior art.